Electric switch



Nov. 29, 1932. H, J. HAM ER Y 1,889,515

ELECTRIC SWITCH Filed June 11, 1952 2 Sheets-Sheet l 1 lll l n 1 I 34 44 42 INVENTOR HERMAN J. H MMERLY,

Nov. 29, 1932. H. J. HAMMERLY ELECTRIC SWITCH Filed June 11, 1932 2 Sheets-Sheet 2 mn i; INVENTOR HERMAN J. yaw,

Patented Nov. 1932 UNITED STATES PATENT OFFICE 3mm J. HAHMERLY, NEW BRITAIN, CONNECTICUT, ASSIGNOR TO THE TRUE- IBULL ELECTRIC MANUFACTURING COMPANY, OF PLAINVILLE, CONNECTICUT, A.

CORPORATION OF CONNECTIOUT ELECTRIC .SWITGH Application filed J'une 1-1,

' My invention relates particularly to en- I closed switches and the construction and arran'gement of the contacting parts and inin which there is no liability of the movable switch member sticking or failing to operate properlg. I Anot er object is to provide a switch construction which is readily adapted for quickmake and quick-break action and in which the correlated parts are so arranged as to permit the switch unit. to be made considerably shorter and more compact than in former similar constructions. In its preferred form the invention contemplates the use of an insulating base with the stationary contacts housed within assages which also guide the movable switch members. Each movable switch member consists of a fiat plate of insulating material having--a perforation in which is loosely mounted a conducting roller. This base is suitably supported by a carrier which 'also supports the operating crank shaft and snap action mechanism for operating the switch.

Fig. l is a front view of aconstructfon emhodyingmy invention as applied to a two pole switch," the stationary contacts and terminals of one of the poles being removed to show the interior construction of the base.

Fig. 2 is a vertical sectional view and end elevation, the parts or the switch being shown in the off or open circuit position.

Fig. 3 is a longitudinal sectional view showing the parts of the switch in the on or closed circuit position. v

Fig. 4 is a side view and section showing one set of stationary contacts, together with the movable switch member and operating crank, the parts being in the open circuitouoff osition.

ig. 5 is an exploded perspective view 1932. Serial so. 818,005.

showing the movable and stationary elements of one pole of the switch.

The main body or insulating base 7 may be formed of any suitable material for the purpose of supporting the conducting members of the switch.

Each switch unit has stationary contacts 8 and 9 of suitable material preferably in the form 0f .bowed springs spaced apart from each other and adapted to receive between them a roller 10 which may be either solid or tubular. The upper contact 8 is provided with a circuit terminal foot or extension 11 secured to the base by a screw 12, and the lower contact 9 has a similar foot 13 secured the'foot ofthe contact 9 and to the base by a screw 17 and. the clip 16 is secured to the circuit terminal 18 by means of a screw 19.

The contacts 8 and 9 are located or housed in recesses such as-20 and 21 and the movable switch member 10 is carried by a flat plate 22 of insulating material having an aperture 23 in which the roller 10 is loosely supported. This plate 22 has its edges guided in grooves 24 between the upper'and lower contacts.

In the closed circuit position the contact roller 10 is tightly gripped between the sprin -1ike upper and lower contacts 8 and 9 but w en the switch is oil the projections 22' on the outer end of the insulating late 22 are positioned between the outer en s of the contact members 8 and 9 as shown in Fig. 4,

and thus hold the plate'in position and prevent the parts from rattling. The contact roller 10 is guided to a certain extent between circuit position and also sothat thespring action will tend to throw the contact roller the shoulders 25, 25 between the recesses 20.

toward the open circuit position as the contact roller leaves the ends of the inclined tips 27.

The insulating base-is provided with pedestals or feet 28 and 29 which are supported on the back plate 30, for instance, by screws 31 and 32. This back plate has a side flange 33,

which two parts serve as a mounting or carrier for the switch contacts and operating mechanism so that the entire switch and its operating mechanism may be handled as a unit. 7 i I i The crank shaft 34 has its opposite ends pivotally supported in the bracket 35 and in the hub 36. This crank shaft is connected to Y x the plates or slides which carry the movable contacts. This connection may, for intance, be efiected by means of a metallic open U-shapedlug 37- which may be riveted or otherwsie suitably secured to the plate 22'.

By removing the screws 31 and 32 the switch block and the contact and terminal members maybe readily removed from the carrier by (simply moving the base upwardly sufiicient to disengage the U-shaped lug 37 from the crank shaft 34. Obviously the parts may be readily assembled in the reverse order.

The back plate serves as an abutment to the contact carryingplates 22 when they are moved to the open circuit position, and the flange 38 of the bracket 35 serves as an abutment for the crank sh'aft 34 when the contacts 10 of the switch are moved to the closed circuit position.

It should be understood that the back plate 30 and the side flange33 are merely illustrated as 'a typical method of installing the switch mechanism in a boxv in the customary manner. This same carrier supports the operating handle 39 which is connected to the hub 36; The disc 40 is supported on the hub j 36 with a lost motion connection of the usual character and is connected to the rod 41 which carries the spring 42 and slides in the abutment plate 43 in the usual way. This disc 40 has lugs 44 and 45 spaced apart from each other and adapted to engage one arm of the crank shaft 34. also in the usual manner.

The operation of the snap action mechanism readily adapts itself to the combination with the switch herein shown and described. It should be understood, however,.'that the invention claimed herein primarily resides in the construction of the stationary. contacts and the movable roller contacts and the meth 0d of supporting and housing the contacts. The insulating slide or plate 22 being flat and merely provided with a perforation or aperture for the contact roller 10 is not only very cheap to manufacture and assemble but produces a compact construction which requires a supporting base of minimum size and maximum simplicity of construction, and which can be readily molded out of insulating material at a minimum of expense. The

duced by pitting of the stationary or movable contacts.

The contact rollers being supported in the insulating plates and guided in the insulating base, there is very little opportunity for arcing and, furthermore, any arc which does tend to form is confined to the base and can not es-- cape outwardly to cause any fire hazard.

The insulating plate and the passage in the base in which it is guided are arranged transversely with respect to the base which makes it possible to provide a mounting means for the roller contact of the cheapest possible form and also makes it possible to mount the stationary contacts 8 and 9 comparatively very close together, thus permitting the base to be made considerably shorter and more compact than former similar switch constructions. The shortening of the base makes it possible to shorten" the enclosing box an equal amount or the'additional space provided in a box of the same length may be utilized as additional wiring space.

I claim: Y 1. In an electric switch, an insulating base having'a transversely extending passage from front to rear with a recess at each-side of the passage, a spring contact mounted in each of said recesses, a 'flat plate guided in the base between said recesses and a roller loosely supported in said plate between said spring contacts.

2. In an electric switch, an insulating base having a transversely extending passage therethrough from front to rear with a recess at each side: of the passage, a contact mounted in each of said recesses, a fiat plate guided in the passage in the base between said recesses and a roller loosely supported in said plate between said spring contacts and guided between walls of said passage.

I 3. In a electricswitch, an insulating base having a transversely extending passage therethroughfromfrontto rear with a recess above and a recess'below the passage, a contact mounted in each of said recesses, a fiat en- ...a.'

plate guided in thebase between said recesses and a roller loosely supported in said plate between said spring contacts, said plate having projecting means for holding the plate in 1 position between the contacts.

4. In an electric switch, an insulating base having a passage transversely extending therethrough from front to rear, spring contacts mounted on opposite sides of said passage, guide grooves in opposite sides of said passage, a flat insulating plate guided in said grooves and having a perforation and a contact roller loosely supported in said perforation and of greater diameter than the thickness of said plate, said passage having shoulders serving as confining guides for the ends of the contact roller.

5. In an electric switch, an insulating base having a passage extending therethrough from front to rear with a recess at each of the opposite sides of said passage, a contact mounted in each of the recesses, guide grooves in opposite sides of said passage, a fiat insulating plate guided'in said grooves and having a perforation and a contact roller loose- 1y supported in said perforation and of greater diameter than the thickness of said plate I for engaging said contacts, said passage having shoulders serving as confining guides for the ends of the contact roller when in its open circuit position.

6. In an electric switch, an insulating base having a transversely extending passage therethrough from front to rear, spring contacts mounted on opposite sides of the said passage, guide grooves in opposite sides of said passage, a flat insulating plate guided in said grooves and having a perforation and a contact roller loosely supported in said perforation and of greater diameter than the thickness of said plate, said contacts having outwardly inclined tips for engaging said roller to hasten the breaking of the circuit.

.7. An electric switch including a supporting back plate, a bracket secured to one edge of the plate and a side plate secured to the opposite edge, an insulating base supported by the back plate, an operating crank shaft pivotally supported by said bracket and said side plate beneath said base, contacts carried by said base, a fiat insulating plate guided to reciprocate through said base between said contacts, a roller loosely carried by said insulat-' ing plate between said contacts, said back plateserving as a rear abutment for said in- V sulating plate.

8. An electric switch including a supporting back plate, a bracket securedto one edge of the plate and a side plate secured to the opposite edge, an insulating base supported by the back plate, an operating crank pivotally supported by said bracket and said side plate beneath said base, contacts *carried by said base, a flat insulating plate connected to said crank and guided to reciprocate 9. An electric switch including a supporting back plate, a bracket secured to one edge of the plate and a side plate integral with the opposite ledge, an insulating base supported by the back plate and having a transversely extending passage with guide shoulders, a crank shaft pivotally supported by said bracket and said side plate beneath said base, contactsv carried by said base at opposite sides of said passage, a flat insulating plate guided to reclprocate in said passage between said contacts, and a roller loosely carried by said insulating plate between said contacts and guided between said shoulders.

10. An electric switch including a supporting back plate, a bracket secured to one edge of the plate and a side plate integral with the opposite edge, an insulating base supported by the back plate, a crank pivotally supported by said bracket and said side plate beneath said base contacts carried by said base, a flat insulating plate connected to said crank and guided to reciprocate through said base between said contacts, a roller loosely carriedv HERMAN J. HAMMERLY.

through said base between said contacts and a roller loosely carried by said insulating plate between said contacts, said bracket having a flange servlng as an abutment for said crank. 

